Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
dat tren » dat trong, dua tren
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va doan » va doanh, van doan, va dan
la tren » loai tren, dua tren, dau tren
y lang » o lang, _ lang, tay lang
va nam » van nam, ha nam, va nay
thu va » thuc va, thue va, tu va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y lang xa hoi. hieu va nam thu va doan va ((la tren) OR (dat tren))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y lang xa hoi. hieu va nam thu va doan va ((la tren) OR (dat tren))".
• Adding a wildcard symbol may retrieve word variants: thu sach y lang xa hoi. hieu va nam thu va doan va ((la tren) OR (dat tren))*.